The PAU Survey

The main aim of PAUS was to measure the redshift of galaxies by photometric methods, with roughly an order of magnitude higher accuracy than that provided by other past or existing photometric surveys, namely with an error in red-shift z of s68=0.0035 (1+z) over an area of about 100 deg2 down to magnitude iAB » 22.5. PAUS was approved in 2007, saw its first light in 2015 and took data at the William Herschel Telescope in La Palma, Canary Islands, during several observational periods from 2015 to 2020. The design and construction of the Camera, its calibration, the data acquisition and processing software and many other technical tasks, were carried out by a small collaboration of five Institutes in Spain, namely from CIEMAT, IFT in Madrid and ICE/CSIC, IFAE and PIC in Barcelona. The culmination of all the technical aspects of the project has been the Public Data Release in 2024 [1]. The data are located at PIC in Barcelona and are part of a very large repository named CosmoHub [2] that includes data from several other major surveys.

PAUS has given rise to about 40 [3] publications in refereed journals and 18 [3] contributions to Conference Proceedings and about [8] Doctoral Thesis, some still in progress. The five Spanish groups in PAUS have been joined by seven other groups from outside Spain, namely from Durham University (the United Kingdom), Leiden Observatory (the Netherlands), Ruhr-Universität Bochum (Germany), University College London (UCL, the United Kingdom), ETH Zurich (Switzerland), the Institute of Cosmology and Gravitation at the University of Portsmouth (the United Kingdom), and Tsinghua University (China).